The present invention relates generally to control of an industrial manufacturing process for manufacturing various models, types and/or specifications of products by means of a single manufacturing line. More particularly, the invention relates to control of manufacturing processes including a step of painting by means of a bar-code label with a plurality of narrower and wider slots the combination of which represents specific binary data, which binary data is representative of the specific model, type and/or specification of the individual product to be produced.
In the automotive industry, various models, types and/or specifications of automotive vehicles are manufactured on a common manufacturing line. The various models, types and/or specifications of the vehicles are transferred through the manufacturing line in order according to a production plan. The manufacturing line consists of various stations for performing different manufacturing operations according to information and instructions corresponding to each of the individual vehicles to be produced. Various vehicle components to be assembled into the corresponding model, type and/or specifications of vehicles are stored at each station. Selection of the corresponding components and assembly of the selected components are performed at each station according to the information and instructions given for each individual vehicle.
For controlling such automotive industry manufacturing operations, a bar-code control system has been developed and proposed. For example, U.S. Pat. No. 4,332,012 to Sekine et al, which has been assigned to the assignee to the present invention, discloses a control system for an automotive vehicle component assembly line employing a bar-code label containing information and instructions relating to model, type and specifications of the vehicle components to be assembled. The disclosure thereof is particularly directed to a sequence of assembly lines for assembling automotive vehicle bodies, which includes a pre-assembly station, a floor assembly line, a body assembly line, a body finishing line and so forth. A bar-code label is formed from a magnetic rubber label on which a bar code is printed. The bar-code label is attached mechanically or magnetically to a sub- or pre-assembly to be applied to the assembly line. This bar-code label must be removed before the assembled vehicle body is fed to a painting process.
In the vehicle body assembly process, the painting process requires various treatment steps for painting the vehicle body which may vary according to differences between the models, types and/or specifications of the vehicle bodies. For example, the vehicle bodies fed to the painting shop may not necessarily require painting in the same color but rather will probably require different colors according to their specifications. Furthermore, special treatment is required when the vehicle body to be painted two-tone. Similar to the vehicle body assembling operation, identification of the body colors of the individual vehicle body and recognition of the required painting treatment for each sequentially fed vehicle body is a very troublesome job. Especially since the painting station consists of a plurality of sub-stations performing only one or two painting steps, it is wasteful to identify which treatments are required at each sub-station.